Cylinders of this general type find multiple uses, particularly in the folding apparatus of a printing press, where the movable tools which are distributed over the cylinder circumference surface can be, for example, spur needle strips, grippers, folding blades, folding jaws or the like. These cylinders are accordingly referred to as spur needle cylinders, gripper cylinders, folding cylinders or folding jaw cylinders.
DE 101 56 194 A1 proposes to reduce the frictional wear of a cover disk tracing or follower roller by providing, in place of one control arm with two such tracing, follower or scanner rollers, two control arms, one of which supports the cam disk scanner roller, and the other of which support the cover disk scanner roller. An abrupt acceleration of the cover disk scanner roller is prevented in this prior art device in that it is maintained in steady contact with the cover roller.